diff --git a/lisp/subr.el b/lisp/subr.el
index 45bcccbb6e5..585ec920458 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1970,7 +1970,7 @@ The value returned is the value of the last form in BODY."
 	'((save-match-data-internal (match-data)))
 	(list 'unwind-protect
 	      (cons 'progn body)
-	      '(set-match-data save-match-data-internal))))
+	      '(set-match-data save-match-data-internal 'evaporate))))
 
 (defun match-string (num &optional string)
   "Return string of text matched by last search.